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I was watching this YouTube video (http://www.youtube.com/watch?v=8FQTabXCh3g) where this guy reshaped his hammers simply using alcohol(w/water) and a soldering iron that has a bent tip shaped like a hammer. He placed a damp cloth over the hammers and steamed each one individually.. He stated it's a non-destructuve method where there is little hammer loss. Anyone familure with this technique? Is this acceptable???

Non-destructive? Not true. Done improperly you can kill a set of hammers faster than you can say mezzo-thermoneal stabilizer!

I suppose if the soldering iron is low wattage - like around 40 watts - it may be safer. But with any technique, it takes practice and experimentation and possibly making some mistakes. So tread carefully...! (unless you love fluffy tone!)

Steaming hammers is an inexact science. If you don't mind hammers that look like potatoes...go for it. I know a tech that steamed a set of brand new hammers on a new Yamaha C7. They exploded! Very expensive lesson. The saving grace was that it wasn't my piano. Now if you are working with the original 90-100 year old hammers that are as hard as the molding which would break your needles...than you don't have much to lose,do you. I guess it can be fun to experiment if there is no $ at stake.

I picked up my espresso machine and turned on the steam wand, and applied this to hammers from one of my grands (it's a light espresso machine so was easy to hold over the hammers). The results were unspectacular.

I had much more success with surface needling (single needle) at a low angle, directly next to and angled under the string grooves (so as to 'fluff up', simply through the insertion of the needle, very lightly the compacted felt in the grooves.)

(I'm an amateur but have voiced my three pianos to my liking and have tried various techniques).

Non-destructive? Not true. Done improperly you can kill a set of hammers faster than you can say mezzo-thermoneal stabilizer!

Done improperly, most anything in life can turn out pretty lethal. From the household to driving your car in traffic.

Ry, what sort of argument is this?

Ron Koval actually gives some commentary on his video, and he shows pretty clearly (to my mind) what he means by "steaming".

Now, rather than trying to discredit his work, I would ask this question:

If the technique that Ron shows is appropriate for "much-used" pianos, e.g. a teaching piano with everyday hard use, with hammers that are only 6 months old, why should it not be appropriate for a 20 or 30 or 40 year old piano that has only been played occasionally by its elderly owner?

Why should a hammer that is only 6 months old, but quite worn, be treated any differently from a hammer that is 40 years old, and similarly worn? Why should we apply special care to a much-used but young piano, as opposed to each piano?

I have colleagues who use this technique to keep the practice and studio pianos at the universities they each service under control. In my direct experience, it works well and quickly but by the time you get the steamer plugged in and filled, you could have the job done by side-needle voicing under the ends of the string marks.

I did what may have been a silly thing that I would like comments on. It has to do with old hammers vs. new hammers. The question is how to tell the difference, both in the hammer and the effect of treatment, since old hammers are not just old, but also well used.

The piano is my own Charles Walter Console about 20-25 years old. When I bought it used a few years ago I did not care for the nasal tone in the low tenor or the brassy sound in the high bass, but thought they could be voiced out. So I tried about everything you could think of in the low tenor including adding weight to the end of the bridge, but was not really happy and ended up taking too much felt off the lowest few hammers trying to undo things that did not work so well. By the way, you can wash hammer hardener out of hammers with acetone, but if they have also been over-needled, there is not much to hold the hammers together.

Too much felt was also taken off the hammers in the high bass, but for a different reason. These hammers were perpendicular to the string plane when on the rest rail, but not when they hit the strings. (It’s a geometry thing.) So to mate the hammers, I filed felt off. The tone still wasn’t right, so I tried re-hanging a few hammers to try to have the hammers meet the strings at a right angle to see if that would help, and it did. So I re-hung all the bass hammers by removing them from the butts and reshaped the bodies as much as I dared for clearance. The hammers still didn’t quite meet the strings properly, but it was much closer and the tone was better. I also had to file even more felt off the high bass to mate the hammers for the new angle, and the result was that the hammers lacked tonal variation.

The piano didn’t sound bad, but I wanted it to sound better and also get the experience of hanging hammers. I had the time, money, and finally some shop equipment. The next question was: which hammers and what side angles?

So I called the fine folks in Elkland and was able to get a set of hammers for the old Pratt-Read action like I had. They were made, I believe, by The American Hammer Company. So these hammers would have the original side angles and if proper care was used in hanging them, there should not be a mating or a clearance problem in the bass, right? The hammers had been sitting on a shelf and were probably about 20 years old. But, so what? Lots of pianos are 20 years old and have 20 year old hammers, right?

The hammers arrived and I sorted out which I wanted for spares and filed the cupping off with first medium and then fine sandpaper. In most of the treble I removed every other hammer and glued the new ones on and then did the same for the others. But in the nasal sounding area above the tenor break I put in new, longer shanks and raised the hammer line going to the break as is done in Asian consoles. I am convinced this helps the nasal tone a great deal.

In the bass I removed all the hammers and left the shanks in place because I had already re-hung the shanks in the butts. When hanging the bass hammers the action was in the piano and the hammers were hung at as much a side angle as possible and still hit both strings of the bichord but, no matter what, also hit the strings squarely. Later, I did have to bend the shanks some and do extensive shaping for clearance, but that is another story…

The result? The bass and low tenor came out OK. The break is not obvious at all, but still a bit nasal. A little side needling helped there. But the mid treble was very percussive. Actually, everything was at least a bit percussive. I will probably not use fine sandpaper when removing the cupping again. It can always be used later, anyway. There was just no dynamics in the treble; everything had the same tone regardless of volume. The tenor and bass weren’t as bad. It sounded like a middle aged console with hard hammers! (No surprise there, duh!)

So now what to do? Well I used what has worked before for me with old, hard hammers: hammer softening solution. And why not? The hammers are hard and stiff from age. Their physical properties have changed due to age, not playing. Why not use something to change the character of the felt instead of trying to un-compact felt with needles or steam, which had never been compacted? I have had to give them a couple of treatments, and may give them another. The alcohol evaporates and some of the hardness, but not all, returns. Of course a little needling was needed here and there to even the tone out.

So if the problem is the hammers are hard from age, I say soften them chemically. If they are hard from compaction, un-compact them with needles and/or steam, especially after reshaping which results in harder felt. And if they are both old and compacted, why not do both?

Comments?

_________________________
Jeff DeutschlePart-Time TunerWho taught the first chicken how to peck?

Non-destructive? Not true. Done improperly you can kill a set of hammers faster than you can say mezzo-thermoneal stabilizer!

Done improperly, most anything in life can turn out pretty lethal. From the household to driving your car in traffic.

Ry, what sort of argument is this?

Ron Koval actually gives some commentary on his video, and he shows pretty clearly (to my mind) what he means by "steaming".

Now, rather than trying to discredit his work, I would ask this question:

If the technique that Ron shows is appropriate for "much-used" pianos, e.g. a teaching piano with everyday hard use, with hammers that are only 6 months old, why should it not be appropriate for a 20 or 30 or 40 year old piano that has only been played occasionally by its elderly owner?

Why should a hammer that is only 6 months old, but quite worn, be treated any differently from a hammer that is 40 years old, and similarly worn? Why should we apply special care to a much-used but young piano, as opposed to each piano?

Anyone?

I have no doubt that Ron Koval knows what he's doing and knows how to get the results he wants in a safe manner. I had no intension of "discrediting" him. I want to make that clear.

I was just taking issue with steaming being a "safe" technique. Like I said before: tread carefully!

Just from a beginners point of view when you have hard hammers that have indentations caused from the strings what is the normal procedure. I imagine shape and needle them. If so, what type of sugar coater do you use. How do you measure what is considered "hard" or how deep do the indentations need to be???

If there is one "safe" method of voicing it is scratch voicing. It can be a pretty quick fix, and it is fairly non-invasive, and is easy to do.

It consists of simply scratching the surface of the hammer with the voicing needle right in the string cuts. First try on the edges of the string cuts, and if you need more contrast scratch the needle along the whole string cut. It's remarkably effective in some cases of harsh tone. It's hard to say how long it lasts, but it can be worth doing in appropriate circumstances.

Just from a beginners point of view when you have hard hammers that have indentations caused from the strings what is the normal procedure. I imagine shape and needle them. If so, what type of sugar coater do you use. How do you measure what is considered "hard" or how deep do the indentations need to be???

When I come across a 25 year old Samick or other similar piano where the tone is really metallic and have string cuts that are a mm or more deep I first try a quick reshaping and then mark the strike point with graphite. Then I go through and deep needle the shoulders at 11 and 1 o'clock being careful to not come up too far on the strike point. The graphite mark is important to know exactly where the strings are connecting with the hammer. If the hammer is stubborn, I come up closer to the top of the hammer trying to keep the needle angled slightly away from the strike point.

I don't do a lot of "sugar coating" but when I do, I use a voicing tool that holds 4 shallow needles. I also have a hammer shank with a row of 5 shallow needles.

I like to follow the voicing with a good pounding while muting the strings out with my hand. Then you can go back over the notes that rebound and are too harsh.

Of course it is important that the hammer to string fit be reasonably good.

I have no doubt that Ron Koval knows what he's doing and knows how to get the results he wants in a safe manner. I had no intension of "discrediting" him. I want to make that clear.

I was just taking issue with steaming being a "safe" technique. Like I said before: tread carefully!

Thanks for the response, Ry - your warning is noted!

In all fairness, however, we should acknowledge that no-one in this thread claimed steaming per sé to be a safe technique. What the thread opener did say/imply, was that Ron presents his own method as non-destructive. And I can see why this should be so: the damp cloth limits the amount of steam that can be released into each hammer. As soon as the cloth has dried under the iron, the steam stops. So, if one(a) wrings the cloth out almost completely, as Ron advises, and(b) gives each hammer just one puff, as Ron shows,then the amount of steam for each hammer must of necessity be very limited.

In this sense, Ron's "self-limiting" method does appear relatively safe to me - but I stand under correction.

Sorry I missed this one! Looks like the points have been covered already -

controlled steam amount by using clothiron hot enough to puff, but not hot enough to burn felt2 step - steam, then 'set' felt with the iron

This technique was shown for the high-use piano - how to keep as much felt on the hammer for as long as possible - reduce the need for regular shaping. Yes, it is true, once the grooves are deep, you can't puff 'em back up.

yamaha hammers, as well as chinese hammers are not real felt, they are held together by some kind of glue.. when steamed they tend to explode as the tension is released and the glue melts.

I can’t claim to be an expert on Yamaha hammers though I’ve certainly voiced a lot of them in a variety of ways, including needling them, steaming them, saturating them with alcohol & water mixtures and god knows what else.

Nor can I claim to be an expert on “chinese hammers” although I’ve designed and pressed some of them and I’ve certainly handled a lot of the felt that goes into making “chinese hammers.” (Whatever that term might mean. I take it to mean hammers that are made in factories located in China.)

To date I’ve never found any “glue” in any of them. Neither in the hammers nor in the felt itself; at least none that was put in there at the factories. Not in the raw felt itself nor in the finished hammers.

Some of these hammers are pressed in ways that result in a lot of felt compression; they are consequently very dense and are relatively heavy. When attempting to drive needles into some of these hammer the density of the felt can certainly make it feel like there just must be a chemical hardener of some kind in there. But, unless we’re discussing chemically saturated NY Steinway hammers, the only thing in there is pure wool. Or, in the case of some of the cheapest hammer felt available—and not just in China—wool and a bit of synthetic fiber acting something like an extender.

Nor have I ever seen a hammer “explode.” And I’ve tried a lot of experimental “voicing” techniques; including steaming. And when I say “steaming” I mean a process that goes well beyond anything shown in the referenced video! I mean steaming!

I’ve been able to get some of these hammers to swell up rather significantly and with rather interesting shapes, but never have I seen one “explode. “ So, I guess I’d like to hear some first-hand descriptions of just what happens when a hammer “explodes.” Even more exciting, I’d like to see some pictures of an exploded hammer or the voicing technique that leads up to its exploding, and then the actual event itself, all recorded by video and posted on YouTube!

So now what to do? Well I used what has worked before for me with old, hard hammers: hammer softening solution. And why not? The hammers are hard and stiff from age. Their physical properties have changed due to age, not playing. Why not use something to change the character of the felt instead of trying to un-compact felt with needles or steam, which had never been compacted? I have had to give them a couple of treatments, and may give them another. The alcohol evaporates and some of the hardness, but not all, returns. Of course a little needling was needed here and there to even the tone out.

So if the problem is the hammers are hard from age, I say soften them chemically. If they are hard from compaction, un-compact them with needles and/or steam, especially after reshaping which results in harder felt. And if they are both old and compacted, why not do both?

Comments?

I still haven't got the confidence to try something like this on a customer's hammers, but I can tell you what I did. I had a brand new Yamaha V-124 with extremely hard hammers, producing a lot of upper partials -> harsh and nasal tone.

This was before my piano tech days, some 5 years ago. I tried to side needle, but with little result. A lot of work though, because getting the through the hammers with a needle was no easy task.

Then I heard about fabric softener and acetone, and logically it made sense. This i used, once, and it opened up the hammers really nicely. After that, good side needling could be done, getting me a pretty good end result.

As I learn about all techniques, subjective preferences and no-no, I realize I would never have pulled that one off if I knew more. Not because of the technique itself, but because I would be scared to death to use it.

BDB said something in a thread half a year ago, about learning voicing as an ongoing process through piano tech life, including ruining a few sets of hammers. I found this comforting

Much about voicing are poster's highly subjective opinions. There is a catch 22 - to succeed in voicing piano hammers you have to be really good at it (practice it) in order not to ruin the hammers. Then, to practice it, you would have to be prepared to ruin hammers.

Trying out all different kinds of suggestions on a set of "disposable" hammers is my way to go, and I'm getting better at it. Lastly, i try to stay imaginative and use common sense. It hasn't gotten me into any major trouble yet

As one of my mentors said to me: Every tuning should include some sort of voicing - even if it is just one hammer.

I have had different phases in my voicing career - back in the late 90's I think I used to overdo it. I'm sure I left some pianos to mushy. I went through my steaming phase and I still think that steaming has its place (even though I haven't used it in quite some time.)

The main thing is try! There are no shortage of old neglected pianos out there! One thing that has really helped me was that years ago I got really fast at reshaping hammers. I frequently do quick reshapings as part of normal piano service.

Another thing is to always have a project piano (or two, or three...) to work on. It gives you complete freedom to do whatever you want to the hammers. Steam them into mush, and then lacquer them back up, then soak 'em with acetone, then file 'em again. See what happens! Learn what the limits are.

There is a certain amount of risk involved with this type of work. The pay-offs are worth it.

I still haven't got the confidence to try something like this on a customer's hammers, but I can tell you what I did. I had a brand new Yamaha V-124 with extremely hard hammers, producing a lot of upper partials -> harsh and nasal tone.

This was before my piano tech days, some 5 years ago. I tried to side needle, but with little result. A lot of work though, because getting the through the hammers with a needle was no easy task.

Then I heard about fabric softener and acetone, and logically it made sense. This i used, once, and it opened up the hammers really nicely. After that, good side needling could be done, getting me a pretty good end result.

As I learn about all techniques, subjective preferences and no-no, I realize I would never have pulled that one off if I knew more. Not because of the technique itself, but because I would be scared to death to use it.

BDB said something in a thread half a year of go, about learning voicing as an on-going process through piano tech life, and includes ruining a few sets of hammers. I found this comforting

Much about voicing is poster's highly subjective opinions. There is a catch 22 - to succeed in voicing piano hammers you have to be really good at it (practice it) in order not to ruin the hammers. Then, to practice it, you would have to be prepared to ruin hammers.

Trying out all different kinds of suggestions on a set of "disposable" hammers is my way to go, and I'm getting better at it. Lastly, i try to stay imaginative and use common sense. It hasn't gotten me into any major trouble yet

For some years I have been presenting classes and seminars on such esoteric topics as “How the Piano Works,” “Understanding the Modern Piano, “Voicing the Soundboard,” or “Voicing the Whole Piano.” The importance of these classes and seminars is generally underestimated. After all, if one is not planning on designing and building new pianos why should it be necessary to know anything about stringing scales or soundboard design? Still, I continue to advocate these classes—and present them at considerable personal expense—because it has long been my belief that the more we know about the instrument we work on the better our work will be and the less damage we will inflict on the poor things. The less mysterious the piano becomes the less fear we will have in trying something new and the more confidence we can have in trying something a bit out of the norm. Not to mention the fact that fewer mistakes based on ignorance will be made.

Understanding the acoustical differences between different types of scales might well keep one from attempting to achieve impossible results and, in the process, causing irreparable damage to the hammers. Understanding the physics of what is happening at the bass/tenor transition might prevent one from over-voicing—and ruining—the hammers in that area when it is really the soundboard system that needs voicing. Indeed, it will open up whole a whole new area of voicing potential techniques; techniques that do not include the hammers at all. Understanding what is really causing that sharp, percussive attack and abnormally short sustain time might prevent destructive and useless hammer voicing techniques and enable one to properly explain to the piano owner what is really making the piano sound that way. And the list goes on….

To use the present case as an example, you do not really need to know that, “Cationic softeners bind by electrostatic attraction to the negatively charged groups on the surface of the fibers and neutralize their charge; the long aliphatic chains are then oriented towards the outside of the fiber, imparting lubricity.” But it is helpful to understand that, quite simply, fabric softeners work by lubricating the felted wool fibers. And thinking about this for a time will be helpful in understanding what effect this might have on the hammer as it impacts the taut strings in a piano.

The more one knows about wool, felt (including the felting process), hammer making and the interaction between the hammers impact against the strings the less mysterious hammer voicing becomes. The idea of treating hammers with fabric softener then becomes a relatively simple decision about whether or not lubricating the surfaces of interlocked and stressed wool fibers in these specific hammers will be beneficial or destructive to the production of piano tone in this particular piano.

I am obviously in favor of experimentation—I certainly do enough of it myself—but as much as possible I try to make this informed experimentation. Otherwise it becomes something like the Edison principle of invention: try everything you can think of and eventually something might work. With luck you might end up with something that works but you’ll have wasted a lot of time and ruined a lot of hammers in the process. And you’ll have learned very little. Having a working knowledge of the materials from which the piano is made—wood, steel and iron, wool, etc.—will give a significant head start in subsequent experimentation. As well, understanding how strings of different physical characteristics vibrate will help one to analyze the sounds heard and will make for much more intelligent voicing choices.

There are lots of things that can give you insight. The other day, I was playing bocce, and someone asked my about my balls, picked one up and dropped on the court. Then he dropped one of his own. (These are metal balls, for volo, not plastic balls.) Mine bounced about 6 inches, while his barely bounced at all. I knew the difference. Do any of you? Do you know how it is related to voicing?